Catalytic converter muffler

ABSTRACT

A catalytic converter muffler has a tubular housing with an inlet and outlet, and a baffle chamber intermediate the length thereof, a generally cylindrical catalytic converter supported in the tubular housing adjacent the inlet and a pair of tubular baffle members are disposed in the baffle chamber. An outlet offset baffle ring closing the inlet end of one of the baffles to block flow of gas thereinto, and an inlet offset baffle element closes the outlet end of the other of the baffles to block flow of gas outwardly to the outlet end of the housing. A power bar is provided in the outlet baffle closely adjacent the outlet end thereof to interrupt the harmonic waves of the base in the outlet baffle. The exhaust gas flows from the catalytic converter into the other baffle and thence through the perforations into the outlet baffle through the perforations in the inlet baffle and through the perforations in the outlet baffle.

BACKGROUND OF THE INVENTION

The present invention relates to mufflers for vehicles and, moreparticularly, mufflers for motorcycles and the like.

In an effort to reduce carbon emissions in the atmosphere, catalyticconverters are required for most vehicles. It is also common,particularly with motorcycles and the like, to provide mufflers thatreduce the noise level and/or alter the frequency of the sound. Therehave been efforts to combine a muffler and a catalytic converter toreduce the package size and to obtain improved results. Indicative of anearly effort in this regard is Wagner U.S. Pat. No. 4,094,664 which wasissued in 1978. However, there has remained a need to develop acombination muffler/catalytic converter construction which is relativelysimple to assemble and relatively long lived.

It is an object of the present invention to provide a novel catalyticconverter muffler with a structure which can be varied in dimensioneasily for different types of vehicles.

It is also an object to provide such an improved muffler to improve gasflow and performance characteristics and to improve fuel consumption andreduce unwanted noise.

SUMMARY OF THE INVENTION

It has now been found that the foregoing and related objects may beattained in a catalytic converter muffler which has a tubular housinghaving an inlet and outlet, and a baffle chamber intermediate the lengththereof. A generally cylindrical catalytic converter is supported in thetubular housing adjacent the inlet, the converter provider flow passagestherethrough. A pair of tubular baffle members is disposed in the bafflechamber, and they have perforations along the length thereof. An outletoffset baffle ring close the inlet end of one of the baffles to blockflow of gas thereinto, and an inlet offset baffle element closing theoutlet end of the other of the baffles to block flow of gas outwardly tothe outlet end of the housing. A power bar is provided in the outletbaffle closely adjacent the outlet end thereof to interrupt the harmonicwaves of the gas in the outlet baffle.

Exhaust gas flows from the catalytic converter into the other baffle andthence through the perforations into the outlet baffle through theperforations in the inlet baffle and through the perforations in theoutlet baffle.

Preferably the baffle members each have an outer wall with an arcuatesection and a generally linear section. At least one tie bar has itsends secured to the baffle elements to assemble the baffle members.Desirably, a pair of tie bars are diametrically spaced apart. Expandingfunnel-shaped inlet members are provided prior to and after thecatalytic converter.

The baffle elements are of generally ring-like configuration and thepower bar extends transversely of the baffle member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a catalytic converter muffler embodyingthe present invention;

FIG. 2 is a partially schematic sectional view thereof;

FIG. 3 is an exploded view of the components;

FIG. 4 is a partially schematic isometric view with the housing removed;

FIG. 5 is an exploded view of the baffle assembly; and

FIG. 6 is a schematic view of the gas flow in the muffler.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now in detail to the attached drawings, the muffler has acylindrical housing 10, an exhaust pipe 12 to be connected to the engine(not shown) and an intake funnel 14. At its other end, the muffler hasan end cap 16. Adjacent the intake end is an expanding funnel 18.

Inserted into the housing is a cylindrical catalytic converter 20 whichis conveniently fabricated from sintered metal. An expanding funnel 22leads the gases into the baffle chamber 24.

In the baffle chamber 24 are perforated baffles 26,27 which areflattened about a portion of their circumference so that they providegenerally flat surface portions 28 while the remainder of thecircumference is arcuate or semicircular 30. At the ends of the baffles26,27 are baffle elements 34,36 of generally circular cross section andwith apertures 38,40 respectively to permit passage therethrough. Thesolid portions block passage of the gas.

The tie bars 42 extend between the baffle elements 34,36 and are securedthereto to couple the baffle members 26,27.

Adjacent the discharge end of the exhaust baffle member 27 is secured apower bar or rod 44 which extends transversely of the flow passage.

In operation, exhaust gas flowing through the pipe 12 flows through thefunnel 18 and into the catalytic converter 20. The gas passing throughthe converter 20 then flows into the baffle member 26. Gas flowingthrough the baffle member 26 is blocked by the baffle element 34 andflows outwardly through the perforations and into the baffle chamber 24and then into the exhaust baffle member 27. Adjacent the exhaust baffleend is the power rod 44 which interrupts the variable pulses in theflowing gas so that the flow is faster and smoother.

As is well known, the baffle chamber is used to reduce the amount ofnoise produced by the motor. To create the right amount of back pressureand retard exhaust flow at the optimum level in order to promote thebest performance of the motor is done by modifying the length of thebaffle pipes, expansion chamber, the size of the baffle chamber, thenumber of perforations in the baffles and their spacing, depth, size andlength.

When the engine exhaust valve opens, it sends a pulse of exhaust out anddown the header rod in rapid succession setting up harmonic waves. Thepower bar brakes the wave and in doing so effects a more rapid flow ofexhaust, thereby improving sound and performance.

Integrating the catalytic converter and baffle into one assembled unit,provides a muffler that reduces noise and pollution while stillimproving performance.

Thus, it can be seen from the foregoing detailed description andattached drawings that the present invention provides a novel mufflerconstruction incorporating a catalytic converter. The placement of thepower bar or rod adjacent the end of the exhaust baffle interrupts theflow waves to improve flow and performance.

1. In a catalytic converter muffler, the combination comprising: (a) atubular housing having inlet and outlet end portions, and a bafflechamber intermediate the length thereof; (b) a catalytic convertersupported in said tubular housing adjacent said inlet end portion, saidconverter providing a flow passage therethrough; (c) a pair of tubularbaffle members disposed in said baffle chamber and extending in parallelrelationship spaced from said housing, said baffle members having asubstantially uniform cross section and perforations along the lengththereof; (d) an outlet offset baffle ring closing the inlet end of oneof said baffle members to block flow of gas thereinto from saidcatalytic converter; (e) an inlet offset baffle ring closing the outletend of the other of said baffle members to block flow of gas outwardlytherefrom to said outlet end of said housing; (f) a power bar in saidoutlet end portion closely adjacent the outlet end thereof to interruptthe harmonic waves of the gas in said outlet; (g) whereby exhaust gasflows from said catalytic converter into the open inlet end of saidother baffle member, is blocked by said outlet baffle ring, said gasthen flowing through said perforations into said baffle chambers intosaid one baffle member through the perforations in said baffle member,said gas then flowing outwardly through the outlet end of said bafflemember.
 2. The catalytic peripheral converter muffler in accordance withclaim 1 wherein said baffle members have a peripheral wall with anarcuate section and a generally linear section, said linear sectionsbeing opposed.
 3. The catalytic converter muffler in accordance withclaim 1 wherein there is included at least one tie bar having its endssecured to said baffle members and baffle rings to assemble said bafflemembers and rings.
 4. The catalytic converter muffler in accordance withclaim 1 wherein there are included an expanding funnel-shaped inletmembers prior to said catalytic converter, and a reducing funnel shapedoutlet member directing the gases into said other baffle member.
 5. Thecatalytic converter muffler in accordance with claim 3 wherein a pair oftie bars are diametrically spaced apart.
 6. The catalytic convertermuffler in accordance with claim 1 wherein said baffle rings are ofgenerally circular ring-like said baffle rings having offset passagestherethrough.
 7. The catalytic converter muffler in accordance withclaim 1 wherein said power bar extends transversely of said outlet endportion.